We proposed a new method for 3D model retrieval based on sketches. As we know a sketch is drawn on a two dimensional plane while models are three dimensional. For better comparison we should choose the same dimension for them. To this end we use three-view drawings to represent 3D models, in this way 3D models can be represented in 2D form. Because three-view drawings are 3 images essentially, we also need three sketches to be compared with them. To calculate the similarity between sketches and three-view drawings of 3D models, Each sketch and three-view drawing are segmented into 16 cells with 4 4 grids. Then we extract a feature vector from each cell using histogram of oriented gradients (HOG). The similarity can be calculated with the distances between feature vectors. Experiments showed that most users can find the 3D models they want with our system.